The job of roughneck or roustabout (someone who performs routine physical labor and maintenance on oil rigs and pipelines) was recently named the worst job in America by CareerCast.com, a job-search site that does a ranking of the best and worst U.S. jobs annually.

Jake Willis, 26, is a roughneck doing maintenance and drill repair for Cactus Drilling in Arnett, Okla., and he loves his job, even though he admits the work is sometimes dangerous.

“I think it’s the best job because it gives people who decide not to go to college a chance to make some decent money,” he said.

What makes a job best or worst? Sometimes it comes down to “brain power vs. brawn power,” said Tony Lee, publisher of CareerCast.com’s 2011 Jobs Rated Report. Many of the worst jobs on the list are physically demanding, have difficult work conditions and often don’t pay well. The jobs that top the list are often a bit cushier, require a degree of some sort and pay higher wages.

Another key component, especially in a tough job market, is availability, Lee noted.

“Not only do they pay terribly, but no one wants to hire you,” he added.

The list changes with the ups and down in the economy as well as societal changes, such as the growing elderly population. Two job categories — roofer and painter — ended up in the bottom 10 for the first time mainly because of the recession’s impact on the construction sector, Lee said. The job of audiologist made the top ten for the first time because of abundant job opportunities and rising salaries.

"The oldest baby boomers are turning 65 and are having hearing problems," Lee noted.

Here’s a rundown of the five worst and best jobs, according to CareerCast, and a look at what the jobs pay, job prospects and working conditions based on CareerCast's research and data from the Bureau of Labor Statistics. We’ll start with the five best.

No. 1 best: Software engineer

Paul Sakuma
/
AP

Job Description: Researches, designs, develops and maintains software systems along with hardware development for medical, scientific and industrial purposes.

Verdict: This low-stress, high-paying job made the top of the list because of “two emerging industries: Web applications and cloud computing. A proliferation of companies making applications for smartphones and tablets, along with the push to develop ‘cloud’ software hosted entirely online, has made the job market for software engineers broader and more diverse,” the report said.

The job brings in about $87,000 annually and the hiring outlook is among the best of the ranking. Positions are expected to increase by about 32 percent by 2018, the fastest of any occupation, according to the BLS.

Job Description: Applies mathematical theories and formulas to teach or solve problems in a business, educational or industrial setting.

Verdict: Kids, you might want to rethink your hatred of math. Mathematicians make the most among the top 10 jobs with an average income of about $95,000, and they enjoy a great work environment and few if any physical demands, according to CareerCast.

At minimum you’ll need a Ph.D for most jobs (and a love for numbers, of course) to join this small group that includes only about 3,000 nationwide right now. That number is projected to rise by 22 percent in the next seven years.

No. 3 best: Actuary

Justin Sullivan
/
Getty Images

Job Description: Interprets statistics to determine probabilities of accidents, sickness, death and loss of property from theft and natural disasters.

Verdict: This job makes the list in part because of the “pleasant” work environment it provides. The salary is pretty pleasant too — about $87,000.

Actuaries typically have a bachelor’s degree, but many also have to take a host of examinations to get full professional standing. Most employers are in the insurance industry. There are about 20,000 actuaries employed in the United States, and the employment outlook is strong. Employment is expected to rise by 21 percent in the next seven years.

Verdict: Most statisticians need a master’s degree in statistics or mathematics, and about 30 percent of those in the field work for government agencies. The job may require long hours and tight deadlines, but it pays $73,208 a year pm average. The number of jobs in this occupation is projected to climb by 13 percent to 25,500 by 2018.

Verdict: These analysts typically work in offices or laboratories and can expect to make about $77,000 a year and enjoy few physical demands at work, other than tiring from sitting too much. Bachelor's degrees aren’t required to do this work, but most employers want one.

There are about 530,000 individuals employed in this type of work, and the job growth outlook for the next few years is above average. The BLS expects the occupation to grow by 20 percent from 2008 through 2018.

No. 1 worst: Roustabout/roughneck

Charlie Neibergall
/
AP

Job description: Performs routine physical labor and maintenance on oil rigs and pipelines, both on and offshore.

Verdict: This job makes its second straight appearance at the top of the worst list. The demanding, dangerous work is what gets the gig its crummy distinction.

“Roustabouts routinely perform backbreaking labor at all hours of the day and night in conditions that can range from arctic winters to desert summers to ocean storms,” the CareerCast jobs report found. “Braving these inhospitable surroundings, roustabouts work on the front lines, getting hands-on with dangerous drilling equipment and risking serious injury or worse — as last year’s explosion at the Deepwater Horizon facility in the Gulf of Mexico illustrates.”

About 60,000 individuals hold such jobs, which typically require little advanced education. Wyoming has the most roustabouts, but Alaska pays the best. Midlevel income for this job averages $32,123, according to CareerCast, but Willis said depending on experience and what they do, roughnecks can make as much as $60,000. Unfortunately job prospects going forward are lousy with a jobless rate upwards of 14 percent.

No. 2 worst: Ironworker

Mark Lennihan
/
AP file

Job Description: Raises the steel framework of buildings, bridges and other structures.

Verdict: This job brings in a bit more money than a lumberjack (see below) at $34,127, but it also requires much more training, as much as four years as a paid apprentice. The work environment is also dangerous and stress levels on this job are high.

The number of iron and metal workers is expected to rise to 110,000 by 2018, up from about 100,000 today, according to the BLS, which expects “many job openings will result from the need to replace experienced ironworkers who leave the occupation or retire.”

Job Description: Fells, cuts and transports timber to be processed into lumber, paper and other wood products.

Verdict: Lumberjacks bring in about $32,000 a year, but despite being in the great outdoors this job can be quite stressful and dangerous and it also rates among the highest when it comes to physical demands.

Logging workers in the United States total about 66,000 and their number is projected to climb by about 4,000 jobs, or 6 percent, by 2018 — below average for most occupations, BLS data show.

No. 4 worst: Roofer

MARCIO JOSE SANCHEZ
/
AP

Job Description: Installs roofs on new buildings, performs repairs on old roofs, and reroofs old buildings.

Verdict: Roofers have been hit hard by tough economic times with only a 4 percent increase in jobs expected over the next seven years, and it’s never been the safest job to have. According to the BLS, “Physical condition and strength, along with good balance, are essential for roofers” and “they cannot be afraid of heights.”

The job typically requires only on-the-job training and income is about $34,000 a year.

No. 5 worst: Taxi driver

Mary Altaffer
/
AP

Job Description: Operates a taxicab over the streets and roads of a municipality, picking up and dropping off passengers by request.

Verdict: Taxi driver ranks the worst when it comes to stress levels, and you get all that angst for a measly $21,127 a year.

Taxi drivers were more likely to be violent crime victims than any other job on the list, said CareerCast’s Lee.

In many states you’ll need a taxi or chauffeur’s license to do this job, and you should enjoy dealing with the public. Most of these jobs are concentrated in big cities, especially in the New York-New Jersey region. Jobs for taxi drivers and chauffeurs are expected to rise by 16 percent by 2018, according to the BLS.